Seduction build question

[bainjs]

With the replacement of the interstate and output caps, the hum has become more noticeable. Do you think the extended leads I had to add to the .1uf KKs to replace the stock caps could have increased the hum?  I used buss wire for the leads.  Could changing from .47uf to 2uf on the outputs increase the hum level?

I guess I can put it back to original and add a set of caps one set at a time to see if I can isolate the hum.

Thanks for your help.

[Doc B.]

With the replacement of the interstate and output caps,

Replacement of the interstate? That might be a Federal crime.

[Grainger49]

Joel put in a pair of KK Teflons for interstage caps and Obbligato Film/Oil for the output caps.

Yes, the extended leads might increase your hum.  What sensitivity speakers do you have.  The higher they are the more likely you are to hear the low level hum that is normal with the Seduction.

You heard my Seduction through 94dBW speakers and 3.5WPC.  My level of hum was normal, you only hear it in abnormal circumstances.  It had 4 of the KK Teflons and 2 Obbligato caps.

Is the Seduction near another piece that it might be picking up hum from?

[bainjs]

Sorry, my iPad has a mind of its own with its spelling correction efforts...

Grainger,

No, it's away from the other equipment.  I'll play with it today.  I've got some suspicions on the hum source to check.   My speakers are 99db .

Thanks

[Doc B.]

Sorry, my iPad has a mind of its own with its spelling correction efforts...

That auto-complete thing on my iPhone was making me crazy. I shut it down. It would be OK if it would just suggest a word and let you decide whether to use it, rather than forcing it on you. Whoever thought of that one must have control issues.

[bainjs]

I removed the KKs and put the stock .1uf caps back in.  I also checked the tube shields to make sure they were well grounded.  Much lower hum, very acceptable.

One other thing, has anyone had their turntable to decide to run backwards?   This is a used SOTA I recently purchased.  I've been playing it without any problems until now.   I couldn't figure out why the leading groove wasn't tracking on the LP to start playing until I noticed the label going counter clockwise.  I kinda had a twilight zone moment seeing that.  I turned the table off and gave it a little push in the right direction and turned it back on.  Seems to be ok now. 

Joel

[Wanderer]

Do SOTAs use a synchronous motor?

If so, there is a start capacitor that creates a phase shift to one of the motor windings that starts it in the right direction. That cap getting out of spec and starting to fail could cause the reverse start from time to time. 

It needs to be the right value of non-polar capacitor but it does not need to be anything more exotic then a mylar type.

I'd contact SOTA and ask what value to use.         

[Grainger49]

Sorry, my iPad has a mind of its own with its spelling correction efforts...

That auto-complete thing on my iPhone was making me crazy. I shut it down. It would be OK if it would just suggest a word and let you decide whether to use it, rather than forcing it on you. Whoever thought of that one must have control issues.

This is a whole 'nother thread.  My brother used to send the most awkward emails from his iPhone (with auto-correct).

[bainjs]

Yes, they use a 24 pole synchro motor.   Thanks for the cap info.  If it becomes an issue, I'll swap it out.

[Grainger49]

Capacitors are a good thing with turntables.  My VIP has a ceramic 0.01uF 1kV across the power switch to keep it from making pops when turning on and off and a 2.0uF 200V to get the motor started.

Good thoughts there Wanderer!

[bainjs]

I replaced the .47uf caps with a pair of KKs donated by Grainger.  No additional hum resulted and they definitely give it a different sound.  A little more body is the way I would describe it.

[Laudanum]

I replaced the .47uf caps with a pair of KKs donated by Grainger.  No additional hum resulted and they definitely give it a different sound.  A little more body is the way I would describe it.

Im trying to remember the Seduction build.  The output caps are .47uF, right?   Are those what you replaced?  I think I used 1.0uF at the outputs, Obbligato golds.  I like them. 

[bainjs]

No, the .47s are the interstage caps.  I used 2uf Obligatos for the output.  I believe the KKs aren't broken in yet, but they already sound pretty good.  It's time to leave it alone and let it play for awhile!

Joel

[Laudanum]

Gotcha.  Stock, the kit is supplied with .47uf for the outputs.  So, I thought maybe you were using the KK's in place of the .47 orange drops or pannys shipped with the kit.  I used the 1.0uf Obbligatos.  I also used them in the FP3 (2.2uf I believe).   Everything sounds great but I havent rolled any other caps to compare. 

[Paul Birkeland]

  I'm getting a faint buzz when the volume is fully up.  Is this typical? 

With your level control all the way up, you are amplifying any noise that might be there A LOT, so yes, this is typical.